The present invention relates to a key-free mouse, more particularly to a mouse having a one-piece top cover pivotally turnable about a longitudinal axis relative to a bottom cover within a suitable degree to touch and thereby actuate a left or a right switch of the mouse.
A mouse is an important peripheral equipment for a computer and has been largely improved in recent years either in its performance or its structural design. For example, a wireless radio-frequency mouse that can be more easily manipulated has been developed to replace a cabled mouse, and a more accurate optical coordinate input means has been developed to replace a ball-type coordinate input means. There is also a mouse having an additional roller-type two-dimensional coordinate input means provided at the top cover for controlling the mouse with a finger. The appearance of the mouse is also frequently changed to attract more consumers. However, as can be found by all consumers, the conventional mouse always has a left and a right key provided at a front end of the top cover. A user moves the mouse with one hand and depresses the left and the right keys with index finger and middle finger, respectively, to control the mouse. This conventional design for a mouse would cause at least the following confusions:                1. The left and the right keys are always arranged side by side at a front end of the mouse, making the top cover of the mouse consisting of at least three parts, namely, two movable keys and one fixed case behind the two keys for supporting a user's palm. Therefore, increased costs are needed to make and assemble different parts of the conventional mouse.        2. The left and the right keys are located at positions corresponding to a user's index finger and middle finger, respectively. It is harmful to a user's index and middle fingers if they are constantly used to depress the left and the right keys for a long term.        3. The two movable keys on the conventional mouse are not freely changeable in their positions and sizes. A big-size key tends to be wrongly depressed, and a small-size key is not convenient for pressing. All users have to handle the conventional mouse in the same manner even the manner is not the best one. There is another commercially available mouse developed for use with an APPLE computer. This type of mouse does not have any key on its top cover, but has a horizontal key provided at a left vertical wall of the mouse depressible with a thumb. The top cover of this type of mouse is provided near an inner rear part with left and right bars for mounting on left and right seats correspondingly provided near an inner rear part of a bottom cover of the mouse, so that the top cover is pivotally turnable about a transverse axis of the mouse relative to the bottom cover. When a front half of the top cover is depressed, it touches and actuates a switch provided in a front space of the mouse. In this design, the rear half of the top cover automatically lifts when the front half is depressed, and a user has to slightly lift his or her palm to suspend over the top cover in response to the lifted rear half. Since this type of mouse is handled in a manner quite different from that usually adopted by most users and is therefore inconvenient for use.        